Method check_rows

_plotly_utils/png.py:647–666

Yield each row in rows, but check each row first (for correct width).

(rows)

        vpr = self.width * self.planes

        def check_rows(rows):
            """
            Yield each row in rows,
            but check each row first (for correct width).
            """
            for i, row in enumerate(rows):
                try:
                    wrong_length = len(row) != vpr
                except TypeError:
                    # When using an itertools.ichain object or
                    # other generator not supporting __len__,
                    # we set this to False to skip the check.
                    wrong_length = False
                if wrong_length:
                    # Note: row numbers start at 0.
                    raise ProtocolError(
                        "Expected %d values but got %d values, in row %d"
                        % (vpr, len(row), i)
                    )
                yield row

        if self.interlace:
            fmt = "BH"[self.bitdepth > 8]